>1500F Elastomer?

[corvuscorax]

Heyo,
I'm using braided carbon fiber cord as a load-bearing member for open-flame lanterns. The carbon cord is directly exposed to open flame at temperatures that exceed 1500F). The carbon stands up to the heat beautifully, indefinitely, but it's poor abrasion resistance leads to failure over time through regular handling and the fastener interface.

I have already tried several aramids: Kevlar, Nomex, Technora and Conex. All char to disintegration far too easily.
I've also tried several glass fibers of various compositions and they invariably shed harmful/irritating particles.

My revisionary plan of action involves compositing the carbon fibers into an elastomeric matrix. I'm hoping to see a resilient barrier which protects the fibers and helps mitigate/isolate progressive fiber deterioration.
Are there any one/two part elastomer compounds that I can use for this application?

Alternatively, I'll have to look for some other way to accomplish the same cord-like texture and mechanical properties in another way. I'd be open to suggestion for anything of that nature too.

It is very important that the cord be very flexible and resistant to high temperature cycles in the order of 1500F-1600F.

Many thanks!
-Corvus

 

[cloa]

See

http://www.eng-tips.com/viewthread.cfm?qid=266897

I'd say no chance.

When you say load-bearing- you mean tensile right?

Maybe you should try real temperature measurements of the cord in operation. Is it bearing the lantern or bearing the filament- how about a diagram.

 

[corvuscorax]

We've measured the temperature of the surface of the burning wick @ just over 1000F with similar numbers along the suspension cord. Max sustained flame temp was measured at 1600F.

Correct, it's primarily a tensile load combined with abrasive interactions between the cord (0.250 dia) and its connection point. Soft flexibility is required due to ergonomic requirements. Basically, this is a large, heavy wick/lantern assembly suspended from a single cord attached directly to the burning wick. It experiences maximum dynamic loads in the order of 100lbs and we'd like to accomplish about twice that in the cord for safety purposes. CF is absolutely ideal in every way except for the poor abrasion resistance. If we could somehow protect it while maintaining the flexibility and low thermal conductivity, we'd be in good shape...A silicone matrix is the closest thing we've seen so far.

Fine-gauge braided stainless steel, something akin to braided solder wick, is an alternative we are considering, but it has much too high thermal conductivity and specific heat capacity...We want to try to keep the cord as cool to the touch as possible - (This is a Cirque application)

Many thanks.
-Corvus

 

[cloa]

I think you should post a new thread in the Materials Engineering Forum linking to this one.

 

[cloa]

You could put some ceramic powder coating on the Fine-gauge braided stainless steel.

 

[johnnymat]

All organic polymers which, includes all rubbers will decompose rapidly at 800 Deg F and above, the hotter it is the faster the decomposition, no matter what filler it may be composited with the polymer matrix will come apart rapidly at these temperatures. The only way to offset this degradtion is to shield it using some ceramic material. but then you have defeated the obfect of having an elastomeric component